''Holy Grail'' wards off all types of flu: scientists

London, Jan 5 (UNI) A super-vaccine that could protect against all forms of flu and proven to be 90 per cent effective has been developed by the British scientists.

Termed the ''holy grail'' of flu treatments, the jab would fight off everything from a winter virus to a bird flu outbreak, researchers said.

Developed by scientists at Cambridge biotech firm Acambis, may also work better than the existing jab, which only protects around three-quarters of those vaccinated.

Flu kills up to 12,000 Britons each year, many of them elderly.

But a pandemic of the human form of bird flu, which many believe is inevitable, could claim 700,000 lives in the UK alone.

Trials on humans show that the jab is safe, causing no side-effects other than the occasional red arm and high temperature associated with all vaccines.

They also show that it works faster to prime the immune system to produce antibodies capable of attacking the virus in upto 90 per cent of those tested.

The trials, carried out on healthy young adults in the US, follow animal experiments in which the jab saved the life of ferrets given a dose of flu strong enough to kill them five times over.

Seventy per cent of vaccinated animals survived, but all those not given the vaccine perished.

Scientists at Acambis are working on perfecting the formulation and dose, ahead of larger scale human trials.

It is thought that two doses a month apart could protect against the bug for many years.

Normally, the vaccine would have to go through another five years of human trials before going on the market.

However, if a bird flu pandemic occurs, it could be made available more quickly.

''Our approach is very simple, it just churns out the vaccine. It is a very elegant approach to production,'' The Daily Mail quoted Dr Michael Watson of Acambis as saying.

The new vaccine, called ACAMFLU-A, is based around a different protein, called M2, which has barely changed during the last 100 years, unlike other vaccines which mutate constantly.

Crucially, it is found in all types of influenza A, including winter flu and the H5N1 bird flu virus.

John Oxford, Britain's leading flu expert, said, ''There is nothing wrong with having a holy grail, something to aim for. If this can be grasped, it would be a wonderful beginning to the new year.'' Professor Oxford, of Queen Mary's School of Medicine in Lonsomedon added, ''Several groups are working on this and one group might have a slightly different formulation and hit the jackpot.'' Professor Ian Jones, a University of Reading virologist, said the jab could end the ''scramble'' to produce a new winter jab each year.

Cautioning that it is still years from the market, he added, ''The fact that the vaccine is safe and appears to raise protective antibodies is very encouraging although larger trials and tests on a wider range of viruses will be needed before the full potential for pandemic protection can be assured.'' News of Acamabis's trials comes only weeks after the inventor of the current flu jab warned it does not guarantee protection. Dr Graeme Laver said the jab left one in four of those vaccinated still be at risk of catching flu.

Talking of the vaccine which he co-developed more than 40 years ago, the Australian said, ''I have never been very impressed with its efficacy. It it better than nothing and I wouldn't want to advise people not to take it, but you can't rely on it.'' He added that best way to protect public health was to make drugs which fight the virus once it has struck, such as Tamiflu and Relenza.